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Workshop => Engine and Bottom End => Topic started by: compton5 on June 30, 2014, 05:38:56 PM

Title: head stay or no head stay
Post by: compton5 on June 30, 2014, 05:38:56 PM
i run a esr 330pv in my 86 I just got done repairing motor mounts and frame from the motor destroying them was wondering if I should run a head stay or not I ride woods only
Title: head stay or no head stay
Post by: Burns363R on June 30, 2014, 05:40:21 PM
Yes you shoudl run one.
Title: head stay or no head stay
Post by: Rupp250 on June 30, 2014, 05:45:12 PM
I run a head stay but I don't have the cylinder head bolt in.
Title: head stay or no head stay
Post by: Burns363R on June 30, 2014, 06:14:22 PM
I dont get what everyone's aversion is to running the head stay bolted in?  Why would anyone consider not using it?
Title: head stay or no head stay
Post by: broken1 on June 30, 2014, 06:23:01 PM
Honda put them there for a reason. just my .02
Title: head stay or no head stay
Post by: johnny22 on June 30, 2014, 07:19:17 PM
I don't run one. I cut the mounts off to shave weight too:)
Title: head stay or no head stay
Post by: Burns363R on June 30, 2014, 08:09:41 PM
Quote from: johnny22;37974
I don't run one. I cut the mounts off to shave weight too:)

Drag racing?
Title: head stay or no head stay
Post by: johnny22 on June 30, 2014, 08:24:19 PM
Yeah
Title: head stay or no head stay
Post by: mandom250r on June 30, 2014, 09:52:38 PM
Quote from: broken1;37971
Honda put them there for a reason. just my .02
i wonder why the aftermarket make heads with out the option for one. i dont run one by the way
Title: head stay or no head stay
Post by: xTHUNDERCATx on June 30, 2014, 10:42:35 PM
Quote from: Burns363R;37970
I dont get what everyone's aversion is to running the head stay bolted in?  Why would anyone consider not using it?

Last time I ran the head stay bolt it broke the mount in half. There could have been other factors but i replaced the mount and left the bolt out for the hell of it
Title: head stay or no head stay
Post by: Bigred on June 30, 2014, 10:49:04 PM
I run mine without the bolt holes don't line up with the cool head
Title: head stay or no head stay
Post by: pinned250r on July 01, 2014, 06:46:29 AM
If you can run it, do it. I added mounts on both of my 89's for the lower rear mount, went with 3/16 steel mounts, that motor is in there solid now.
Title: head stay or no head stay
Post by: mennis1971 on July 01, 2014, 07:13:11 AM
I run one also. It didn't line up with my cool head, so I put a smaller bolt in it. Now that I have a spacer plate motor, it lines up LOL. Still using the small bolt tho. Have another coolhead where the bolt hole isn't slotted like my newer one. They also made some with no head stay mount. Part of the reason I haven't built my LSR frame is that it didn't come with a headstay from it's PO. He just raced flat track with it btw. Whether you choose to bolt it to the motor or not, I do believe it's important to bolt it to the frame at least to help stop frame flex/stress.
Title: head stay or no head stay
Post by: Bio86 on July 01, 2014, 08:15:49 AM
I've always wondered this as well.  Always ran one but have cracked/broke every single mount on my bike. Remade the lower bolt-on mounts out of .250" Aluminum, remade the middle lower mounts because they both broke off, fixed the head stay and now it's cracking around the lower square tubing down by the foot pegs and right in front of the middle lower mounts.    Has to be a vibration thing in my case because I just do light dune riding, maybe the bike is reaching its' natural frequency with larger bores and beating itself up like the Tacoma Narrows bridge!!
Title: head stay or no head stay
Post by: pinned250r on July 01, 2014, 08:36:12 AM
I don't think the type of riding plays a major role in the motor mounts breaking. Obviously other frame tweaks are caused by different types, but at the end of the day, I thinks it's all due to our high performance engines vibrating the heck out of us that causes the breaks. I just repaired all of my mounts this winter. It's something that is just gonna keep happening I think, even tho I added an extra mount and thickened all the others
Title: head stay or no head stay
Post by: Tbone07 on July 01, 2014, 09:15:35 AM
If you can run the head-stay WITHOUT torquing the head to one way or the other, then run it. Don't force the head to line up with the head-stay.

My head-stay lines up perfectly with my head, but the bolt hole doesn't.....if that makes sense. So I choose to run the head-stay.
Title: head stay or no head stay
Post by: ytman on July 05, 2014, 09:08:51 PM
I would like to know LSRs take on the head stay. I don't think I've seen one of their units go one ride without a fracture
Title: head stay or no head stay
Post by: mennis1971 on July 05, 2014, 09:13:09 PM
While I don't have a headstay for my lsr, I've seen others and they sure don't look very strong IMHO
Title: head stay or no head stay
Post by: atvmxr on July 07, 2014, 02:01:48 PM
Quote from: Burns363R;37970
I dont get what everyone's aversion is to running the head stay bolted in?  Why would anyone consider not using it?

i dont run it on my Rs or my zillas.  eons ago, the thought was the headstay kept the motor from reving as freely.  When the motor torques, the headstay keeps the cylinder from being able to move with the motor.  in theory, this causes increased side load on the piston and limits its ability to rev as easily.   on the zillas the headstay will cause the headgasket to start leaking
Title: head stay or no head stay
Post by: wilkin250r on July 10, 2014, 06:15:34 PM
I've heard quite a few arguements on both sides, and the general rule of thumb seems to be whichever is more important to you, motor or chassis.

The drag guys run without it.  It saves that much weight, and they claim it lets the motor rev free, and fewer blown head gaskets due to that much less stress on the head and head bolts.  The drag guys generally aren't worried about chassis issues, they're much more concerned about their motors.

The MX guys talk about breaking more motor mounts and more frame cracking without the head stay.  The head stay doesn't eliminate all frame cracking and issues, but they claim it's certainly worse without it.  The MX guys aren't pushing max horsepower, they're generally more concerned with their chassis than their motor.

I think that's what it boils down to.  Which are you more concerned about?  Chassis or motor?